Hey all -- still working on getting a new to me bike ride-able -- thought I had it were I could ride to work -- but it died at highway speed and left me stranded. left me stranded. Tow truck to house.
Problem: recent past it rides fine at lower speeds -- at highway speeds it starts to cut out, feels like a surge but more likely the enginer was just cutting out. worked on it over the weekend and thought it was better. rode to work and still felt the cutting out at 65-80MPH and associated RPM. uncomfortable but still functioning. then on ride home, Hot humid day, It started cutting out and then just fully cut out, had to coast off Highway. got it going on service road and tried to ride home slow on back roads since below 45 it has been fine, but then the engine cut out again and left me stranded. Battery fine and it would still crank via starter, but would not start up. let it cool some, but still would not start. tow truck got me home, once in the garage it started up pretty easy, and will start now. Im at a bit of a loss. Hope someone can say, "yep, seen this and your problem is this"
2002 vmax
- battery is charging 13.5 V (not great but the battery is still turning the engine over). Battery never died through the whole stranding -- I kept trying to start for 1.5 hrs while waiting for tow truck. Starter kept turning over engine but no fire, engine just turned but no vroommm, then started the bike once off the tow truck. I did try choke on and off several times as the bike cooled.
- temp was good the whole time
- when by the road, I didn't ever hear the Fan (???) --- but temp was showing moderate, a little above midpoint.
- checked stator and shunt R/R last weekend -- they are fine
- RR run straight to pos terminal. crimp removed, cleaned all contacts and applied elec grease to all connectors between stator and battery and cleaned ground connections.
- new speak plugs. plug wired appear in good shape --- descent spark on the plugs
- good fuel
- synced carbs last weekend -- seemed better but then problem started creeping back in and got progressively worse.
- new fuel filter -- cut old one open and did not find rust.
- compression good -- checked last week before I changed plugs
- Air filter is clean
- RPM does not seem to matter -- can rev up at lower speeds in lower gear and seems to have no issue -- when its not completely cut out.
- thinking back, seems that it cuts out when I release the throttle or slow down if Im going at any kind of speed. i.e., going fast, let off the throttle, and engine seems to cut out, and takes a moment to start pushing again. Perhaps the engine was in fact dying when I let off, but momentum of the bike "push started" it again after 2-3 seconds. dunno.
need 4 things: compression/fuel/spark/air
- compression is good
- I think spark is good -- but could not check when I was by the road.
- leaves me with fuel and Air.
suspicions:
- Fuel -- perhaps the aftermarked fuel pump -- should I get a OEM fuel pump (not cheap if current one is fine)
- Air -- have not rebuilt carbs yet or even dug down into them -- but works at lower speed up to around 55ish in any RPM
- spark- ??? reasoning thats not it, if it was one plug or coil, then other three would have started bike or kept it going -- I would have had the bike at least try to fire -- something killed the whole system -- is there something between all four coils and the battery that could go wrong.
- odd thought -- removed crimp and replaced with butt splice that has the solder in the butt connector -- when I replaced the crimp it didn't look bad. possible the butt splice connection I made was not good and I should solder in wire and shrink wrap. but to me seems unlikely given it runs ok at lower speeds.
goign to start trouble shooting -- will probably replace fuel pump just to rule that out. then open up the carbs and start poking at those. bike had mostly sat for 2 years prior to my purchase a few weeks ago. I drove it home from purchase site (5 hrs highway). was cutting out then as well, but made it all the way home.
Thanks for any solid leads. Brett
Problem: recent past it rides fine at lower speeds -- at highway speeds it starts to cut out, feels like a surge but more likely the enginer was just cutting out. worked on it over the weekend and thought it was better. rode to work and still felt the cutting out at 65-80MPH and associated RPM. uncomfortable but still functioning. then on ride home, Hot humid day, It started cutting out and then just fully cut out, had to coast off Highway. got it going on service road and tried to ride home slow on back roads since below 45 it has been fine, but then the engine cut out again and left me stranded. Battery fine and it would still crank via starter, but would not start up. let it cool some, but still would not start. tow truck got me home, once in the garage it started up pretty easy, and will start now. Im at a bit of a loss. Hope someone can say, "yep, seen this and your problem is this"
2002 vmax
- battery is charging 13.5 V (not great but the battery is still turning the engine over). Battery never died through the whole stranding -- I kept trying to start for 1.5 hrs while waiting for tow truck. Starter kept turning over engine but no fire, engine just turned but no vroommm, then started the bike once off the tow truck. I did try choke on and off several times as the bike cooled.
- temp was good the whole time
- when by the road, I didn't ever hear the Fan (???) --- but temp was showing moderate, a little above midpoint.
- checked stator and shunt R/R last weekend -- they are fine
- RR run straight to pos terminal. crimp removed, cleaned all contacts and applied elec grease to all connectors between stator and battery and cleaned ground connections.
- new speak plugs. plug wired appear in good shape --- descent spark on the plugs
- good fuel
- synced carbs last weekend -- seemed better but then problem started creeping back in and got progressively worse.
- new fuel filter -- cut old one open and did not find rust.
- compression good -- checked last week before I changed plugs
- Air filter is clean
- RPM does not seem to matter -- can rev up at lower speeds in lower gear and seems to have no issue -- when its not completely cut out.
- thinking back, seems that it cuts out when I release the throttle or slow down if Im going at any kind of speed. i.e., going fast, let off the throttle, and engine seems to cut out, and takes a moment to start pushing again. Perhaps the engine was in fact dying when I let off, but momentum of the bike "push started" it again after 2-3 seconds. dunno.
need 4 things: compression/fuel/spark/air
- compression is good
- I think spark is good -- but could not check when I was by the road.
- leaves me with fuel and Air.
suspicions:
- Fuel -- perhaps the aftermarked fuel pump -- should I get a OEM fuel pump (not cheap if current one is fine)
- Air -- have not rebuilt carbs yet or even dug down into them -- but works at lower speed up to around 55ish in any RPM
- spark- ??? reasoning thats not it, if it was one plug or coil, then other three would have started bike or kept it going -- I would have had the bike at least try to fire -- something killed the whole system -- is there something between all four coils and the battery that could go wrong.
- odd thought -- removed crimp and replaced with butt splice that has the solder in the butt connector -- when I replaced the crimp it didn't look bad. possible the butt splice connection I made was not good and I should solder in wire and shrink wrap. but to me seems unlikely given it runs ok at lower speeds.
goign to start trouble shooting -- will probably replace fuel pump just to rule that out. then open up the carbs and start poking at those. bike had mostly sat for 2 years prior to my purchase a few weeks ago. I drove it home from purchase site (5 hrs highway). was cutting out then as well, but made it all the way home.
Thanks for any solid leads. Brett
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